I live in Central Florida (Orlando Area) and have a St. Augustine Grass lawn at my home. The lawn has always been a problem since I purchased the home several years ago. When I first moved in, the front lawn was in poor condition as the previous residents had moved out months before and it had not been watered/cared for since that time. I began a normal mowing/watering/fertilizer regimen according to the local extension office guidelines but after about a year the majority of the front lawn was dead. I had it replaced with fresh St. Augustine Sod but found after it was installed that the sod appeared to be old and was largely brown. Watered it as much as possible and most of it appeared to come back to green. Fast forward to now (about 14 months since sod replacement) and I am again facing the same problem. The front lawn is largely brown and patchy (bare spots now appearing) no matter how much I water it.

So let me go through the steps I have already taken in the last few years with this lawn:

1. I had the soil tested at a lab to determine fertilizer needs. The results were:

PH: 8.3
Phosphorus 45 PPM
Potassium 28 PPM
Magnesium 83 PPM
Calcium 2264 PPM

Fertilizer Recommendations were:
Nitrogen 2 LBS/1000 Sq. Ft
Potassium 1 LBS/1000 Sq. Ft

2. Inspected & Tested sprinkler irrigation system to ensure watering time provided adequate water for grass.


3. Ensured that mowing was done at proper height and time to ensure grass health.

4. Fertilize according to recommendations above and schedule from extension office.

None of the steps I have taken seem to have helped. The front lawn is still largely covered with brown blades of grass, bare spots are again showing and weeds seem to be popping up frequently. Can anyone offer some advice here?

 

Have you ever had the soil aerated? A good core aeration couldn't hurt.

What is your watering and fertilizer schedule?

 

Do you have trees in your yard or animals that might have an impact on the lawn? Have the brown spots been green or are those the areas that never did look healthy? I used to work in Orange and Seminole counties and have seen a lot of sod [both St Augustine and Bahia] go down that looked iffy but for the most part it would all come back with good watering.

 

I've never had the soil aerated nor have I de-thatched the lawn in the time that I've lived here. I was considering doing both of these in the next few weeks but was concerned that it wouldn't make any difference as the grass seems pretty far gone. I calibrate my sprinklers several times a year to ensure that the watering time is providing the required amount of water to each area of the lawn. I water it twice a week (all that is allowed by our water restrictions) for 45 minutes each time. I fertilize according to the high maintenance grass schedule from UF IFAS (extension office) which in general provides for 5-6 fertilizer applications per year.

As for animals and trees in this area of the yard: I have no animals nor do any of my immediate neighbors. Trees however are another story: I have two large trees in the front yard in the same area of the grass. I also have ficus hedges in front of the house along the foundation. I have been considering removing both the trees and the hedges this year as I don't like either of them. I am assuming that the best course of action here would be to remove the trees, de-thatch and then aerate the lawn?

 

I don't have a lot of familiarity with warm season grasses since they don't grow up here but is St. Augustine a grass which needs de-thatching? Most don't but I know there are a couple warm seasons grasses which can develop thatch, most often if they are over-fertilized. That said, a core aeration is usually sufficient for thatch problems as well as soil compaction so I don't think you need to de-thatch.

How much water are you putting on the lawn when the sprinklers run for 45 minutes? For what it's worth, twice a week is plenty for watering, the rule of thumb is infrequent deep waterings, as frequent light waterings promote shallow root growth.

 

From my understanding, St. Augustine sometimes needs de-thatching. I have noticed some buildup of dead clippings on the soil below the blades of grass in this area of the lawn. I believe that the clippings aren't breaking down quick enough between mowings which is allowing them to build up. As for the watering, the general rule of thumb here is 1" of water for the grass per watering. When I calibrated the sprinklers I set out flat bottom containers (identical ones) scattered throughout each area of the sprinkler zone. I then used them to determine how long it took to get an average of 1" of water for each zone which for this area of the lawn was 45 mins.

 

1" sounds good, your watering sounds alright.

Grass clippings are not thatch, thatch is a buildup of lower material, more like stems. That said, leaving the clippings on the lawn is the right thing to do, glad to hear you're doing that.

Ok, we've eliminated most of what I thought of, I'm back to a core aeration.

That said, some pictures couldn't hurt, can you post a couple?

 

I took a couple of photos, let me know what you think.

 

It looks thin, that's for sure, but it seems like there's enough green to give bringing it back a shot.

 

Good to hear that it's not a total loss. Over the next couple of weeks I am going to get rid of the two trees, aerate, water, fertilize and hope for the best. I'll keep y'all posted and am still open to any further ideas/suggestions.